Music for work (or whatever)
Magatune lets you listen to songs for free. If you want to download, you set the price. When you do pay, half the amount you pay goes to the artist, and you have the opportunity to make your email address visible to the artist, so you might even end up in a discussion!
Finally, if you're trying to use it in a commercial setting (restaurant, art gallery, training class, Web site, or whatever), they have an easy, automated way to calculate the required payment and to pay online.